lture hero of the Nahuas,
_Quetzalcoatl_ (feathered serpent) corresponds to a similar god among
the Mayas, _Kukulcan_ (also meaning feathered serpent). The feathers of
the quetzal are the ones commonly used in connection with the serpent.

Any attempt at identification of the species represented is beset by
grave difficulties for so conventionalized have the figures often become
that, except in the case of the rattlesnake with its rattles, there are
no characteristic marks by which the species may be known. It is natural
to suppose that the species used for artistic purposes would be those
that are most noteworthy because of their size, coloring, or venomous
qualities. No doubt a number of harmless species were also used in the
religious ceremonies.[311-*] Such may be those used as hair ornaments in
many of the figures (Pl. 8, figs. 7-13, 15) and in which no indication
of a rattle is to be seen. The fierce eye of these reptiles is shown by
means of an exaggerated overhanging brow occasionally embellished by
recurved crests (Pl. 8, figs. 10, 11, 13, 15). These crests are
sometimes shown as two or three stalked knobs (Pl. 10, fig. 7) that
Stempell was misled into identifying as the eyes of snails. Various
heads of snakes usually with fangs exposed and tongue protruding are
pictured in Pl. 8, figs. 4, 6; Pl. 9, figs. 2, 4-6: one snake with a
spiny back is shown in Pl. 8, fig. 5, but obviously it represents merely
the artist's endeavor to present as terrifying a creature as possible.

Various types of rattlesnakes are shown in Pl. 9. The presence of the
rattle is of course the characteristic, and this portion alone is
likewise used, in one case, at least, as a glyph (Pl. 9, fig. 7). It
cannot be denied, however, that some or most of the snakes in which no
rattles appear, are nevertheless intended for rattlers. It may have been
that the figures were so well understood that the addition of rattles in
the drawings was quite unnecessary. This, however, is quite conjectural.
The species of rattlesnake is probably _Crotalus basiliscus_ or _C.
terrificus_ of southern Mexico and adjacent regions, not _C. horridus_
or _adamanteus_ as supposed by Stempell since these two species are
confined to the United States. Among the figures shown on Pl. 9, it is
noteworthy that five of the rattlesnakes show no fangs. Some are
spotted, but in a wholly arbitrary manner. Three are unmarked. One is
shown coiled about the base of a tree (Pl. 9, fig